Light-emitting device, preparation method thereof and display device

Abstract

The invention discloses a light-emitting device, a preparation method thereof and a display device, and relates to the technical field of display. The light-emitting device comprises a first electrode, a light-emitting layer and a second electrode which are stacked, and the material of the light-emitting layer comprises nanoparticles; the light-emitting device further comprises a first carrier functional layer and a passivation layer, one of the functional layers between the first electrode and the second electrode contains a passivator, the passivator comprises an AX compound, A is selected from R-COOH <->, and X is selected from lithium ions, metal ions of IIA group elements or metal ions of IIB group elements. According to the light-emitting device provided by the invention, the A ions in the passivating agent are used as an electricity-rich Lewis base and can be combined with defects containing positive charges on the surfaces of the nano-particles, the defects are passivated, the performance of the nano-particles is improved, and quantum dots are promoted to emit light; the X ions in the passivator are small in ion radius, so that the defect that the surfaces of the nanoparticles contain negative charges can be passivated, the power consumption of the light-emitting device is reduced, and the light-emitting efficiency of the light-emitting device is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a light-emitting device, a method for preparing the light-emitting device, and a display device including the light-emitting device. Background Art

[0002] Currently, the widely used light-emitting devices are organic light-emitting diodes (OLEDs) and quantum dot light-emitting diodes (QLEDs). OLED has become the mainstream technology in the field of display technology due to its excellent display performance, such as self-luminescence, simple structure, ultra-thinness, fast response speed, wide viewing angle, low power consumption, and flexible display. QLED has the advantages of saturated color and adjustable wavelength of emitted light, and high quantum yield of photoluminescence and electroluminescence, and has become a strong competitor of OLED in recent years.

[0003] The structure of traditional OLED and QLED devices generally includes an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer and a cathode. Under the action of the electric field, the holes generated by the anode of the light-emitting diode and the electrons generated by the cathode move and are injected into the hole transport layer and the electron transport layer respectively, and finally migrate to the light-emitting layer. When the two meet in the light-emitting layer, energy excitons are generated, thereby exciting the light-emitting molecules and finally producing visible light.

[0004] At present, the luminous efficiency of light-emitting devices is relatively low and needs to be further improved. Summary of the invention

[0005] In view of this, the present application provides a light-emitting device, aiming to improve the problem of low light-emitting efficiency of existing light-emitting devices.

[0006] The embodiment of the present application is implemented as follows: a light-emitting device comprises: a first electrode, a light-emitting layer, and a second electrode which are stacked, wherein the material of the light-emitting layer comprises nanoparticles;

[0007] The material of the light-emitting layer includes a first passivator; or

[0008] The light emitting device further comprises a first carrier functional layer, the first carrier functional layer is arranged between the first electrode and the light emitting layer, and the material of the first carrier functional layer comprises a second passivator; or

[0009] The light emitting device further comprises a first carrier functional layer and a passivation layer, wherein the first carrier functional layer is arranged between the first electrode and the light emitting layer, the passivation layer is arranged between the first carrier functional layer and the light emitting layer, and the material of the passivation layer comprises a passivation material;

[0010] The first passivator, the second passivator and the passivation material are independently selected from one or more of AX compounds, the A is selected from R-COOH-, the R is H or an alkyl group with 1 to 5 main chain carbon atoms, and the X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements.

[0011] Optionally, in some embodiments of the present application, the AX compound includes one or more of magnesium acetate, zinc acetate, and lithium acetate; and / or

[0012] The first carrier functional layer is a hole functional layer or an electron functional layer.

[0013] Optionally, in some embodiments of the present application, the mass ratio of the first passivator to the nanoparticles is 1:(1-5); or

[0014] The material of the first carrier functional layer also includes a first carrier functional material, and the mass ratio of the second passivator to the first carrier functional material is 1:(2-10).

[0015] Optionally, in some embodiments of the present application, the light-emitting device further includes a second carrier functional layer, the second carrier functional layer is arranged between the light-emitting layer and the second electrode, and the second carrier functional layer is an electron functional layer or a hole functional layer.

[0016] Optionally, in some embodiments of the present application, the nanoparticles include quantum dots, and the material of the quantum dots includes CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnS eS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS , SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, GaN, GaP, GaAs, GaSb, AlN, AlP , AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb , InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlN As, InAlNSb, InAlPAs, InAlPSb, CuInS2, CuInSe2, AgInS2, CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnS One or more of eS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS, InP / ZnSe / ZnS, AMX3 and BMX3, where A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge2+ , Yb 2+ 、Eu 2+ One or more of the following, X is a halogen anion selected from Cl-, Br - ,I - One or more of; B is an organic amine cation selected from CH3(CH2) n- 2NH3 + or [NH3(CH2) n NH3] 2+ , where n ≥ 2; and / or

[0017] The material of the electronic functional layer includes one or more of doped or undoped semiconductor particles, quinoxaline compounds, imidazole compounds, triazine compounds, fluorene compounds, and hydroxyquinoline compounds; the semiconductor particles include one or more of zinc oxide, barium oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, tungsten sulfide, copper sulfide, zinc selenide, indium phosphide, gallium phosphide, and barium titanate; the doped elements include one or more of indium, gallium, aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium; and / or

[0018] The material of the hole functional layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tri(N-carbazolyl)-triphenylamine, 4,4',4'-tri(carbazol-9-yl)triphenylamine, trichloroisocyanurate, Acid, terbium-doped phosphate-based green luminescent materials, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene [vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amines, polynuclear aromatic tertiary amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N'-diphenyl Benzidine, spiro NPB, nano-polycrystalline diamond, microcrystalline cellulose and tetracyanoquinodimethane, doped graphene, undoped graphene, transition metal oxides, transition metal sulfides, transition metal tin compounds, doped or undoped zinc oxide, barium oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, lithium zinc oxide, indium tin oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, tungsten sulfide, copper sulfide, zinc selenide, indium phosphide, gallium phosphide, copper indium sulfide, copper gallium sulfide, barium titanate, quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, hydroxyquinoline compounds, or one or more thereof; and / or

[0019] The materials of the first electrode and the second electrode each independently include one or more of metal, carbon material and metal oxide; the metal includes one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb and Mg; the carbon material includes one or more of graphite, carbon nanotubes, graphene and carbon fiber; the metal oxide includes a metal oxide electrode or a composite electrode with a metal sandwiched between doped or undoped transparent metal oxides, the material of the metal oxide electrode includes one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3 and AMO, and the composite electrode includes one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2 and TiO2 / Al / TiO2.

[0020] Optionally, in some embodiments of the present application, the average particle size of the nanoparticles is 5 nm to 15 nm; and / or

[0021] The thickness of the light-emitting layer is 10 nm to 20 nm; and / or

[0022] The thickness of the electronic functional layer is 30nm to 50nm; and / or

[0023] The thickness of the hole functional layer is 10nm to 30nm; and / or

[0024] The thickness of the passivation layer is 0.01 nm to 5 nm; and / or

[0025] The thickness of the first electrode and the second electrode are independently 30 nm to 40 nm.

[0026] Accordingly, an embodiment of the present application further provides a method for preparing a light-emitting device, comprising:

[0027] Providing a light-emitting device preform, wherein the light-emitting device preform comprises a first electrode;

[0028] forming a light-emitting layer on the first electrode, comprising: providing nanoparticles and a first passivator, and arranging the nanoparticles and the first passivator on the first electrode to form the light-emitting layer; or

[0029] Forming a first carrier functional layer on the first electrode, comprising: providing a first carrier functional material and a second passivator, and arranging the first carrier functional material and the second passivator on the first electrode to form the first carrier functional layer; or

[0030] The light emitting device preform further includes a light emitting layer disposed on the first electrode, and forming a first carrier functional layer on the light emitting layer includes: providing a first carrier functional material and a second passivator, and disposing the first carrier functional material and the second passivator on the light emitting layer to form the first carrier functional layer; or

[0031] The light emitting device preform further includes a first carrier functional layer disposed on the first electrode, and forming a passivation layer on the first carrier functional layer includes: providing a passivation material, and disposing the passivation material on the first carrier functional layer to form the passivation layer; or

[0032] The light emitting device preform further comprises a light emitting layer disposed on the first electrode, and forming a passivation layer on the light emitting layer comprises: providing a passivation material, and disposing the passivation material on the light emitting layer to form a passivation layer;

[0033] Wherein, the first passivator, the second passivator and the passivation material are independently selected from one or more of AX compounds, the A is selected from R-COOH-, the R is H or an alkyl group with 1 to 5 main chain carbon atoms, and the X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements;

[0034] A second electrode is formed on the first carrier functional layer, the light emitting layer or the passivation layer to obtain a light emitting device.

[0035] Optionally, in some embodiments of the present application, the AX compound includes one or more of magnesium acetate, zinc acetate, and lithium acetate; and / or

[0036] The first carrier functional layer is a hole functional layer or an electron functional layer.

[0037] Optionally, in some embodiments of the present application, the forming of the light-emitting layer comprises: mixing the nanoparticles, the first passivator and the first solvent to obtain a first dispersion, and disposing the first dispersion on the light-emitting device preform to form the light-emitting layer; or

[0038] The forming of the first carrier functional layer comprises: mixing the first carrier functional material, the second passivator and the second solvent to obtain a second dispersion, and disposing the second dispersion on the light emitting device preform to form the first carrier functional layer; or

[0039] The forming of the passivation layer comprises: providing a passivation material, dissolving the passivation material in a third solvent to obtain a passivation material solution, and disposing the passivation material solution on the light emitting device preform to form the passivation layer.

[0040] Optionally, in some embodiments of the present application, in the first dispersion, the mass concentration of the nanoparticles is 5 mg / mL to 20 mg / mL; and / or

[0041] In the first dispersion, the mass concentration of the first passivator is 2 mg / mL to 20 mg / mL; and / or

[0042] In the first dispersion, the mass ratio of the first passivator to the nanoparticles is 1:(1-5); and / or

[0043] In the second dispersion, the mass concentration of the first carrier functional material is 10 mg / mL to 50 mg / mL; and / or

[0044] In the second dispersion, the mass concentration of the second passivating agent is 5 mg / mL to 20 mg / mL; and / or

[0045] In the second dispersion, the mass ratio of the second passivator to the first carrier functional material is 1:(2-10); and / or

[0046] In the passivation material solution, the mass concentration of the passivation material is 2 mg / mL to 20 mg / mL; and / or

[0047] The first solvent, the second solvent, and the third solvent respectively include one or more of ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0048] Optionally, in some embodiments of the present application, after the passivation layer is formed, annealing is further included, the annealing temperature is 80° C. to 160° C., and the annealing time is 5 min to 60 min.

[0049] Correspondingly, an embodiment of the present application further provides a display device, which includes the above-mentioned light-emitting device, or the light-emitting device manufactured by the above-mentioned manufacturing method.

[0050] The light-emitting device provided by the present application comprises a material of a light-emitting layer in the light-emitting device comprising quantum dots, a light-emitting layer or a first carrier functional layer or a passivation layer in the light-emitting device comprising a passivator, the passivator comprising an AX compound, A being selected from R-COOH-, X being selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements, the passivator being capable of combining with nanoparticles, the A ions in the passivator being an electric-rich Lewis base, being capable of combining with defects containing positive charges on the surface of the nanoparticles, passivating the defects, improving the performance of the nanoparticles, and promoting the luminescence of the nanoparticles; the X ions in the passivator having a small ion radius, being capable of effectively passivating defects containing negative charges on the surface of the nanoparticles, further reducing the power consumption of the light-emitting device, improving the luminescence efficiency of the light-emitting device, and extending the service life of the light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0052] Figure 1 is a schematic structural diagram of a light-emitting device provided in an embodiment of the present application;

[0053] Figure 2 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

[0054] Figure 3 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

[0055] Figure 4 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

[0056] Figure 5 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

[0057] Figure 6 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

[0058] Figure 7 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

[0059] Figure 8 It is a flow chart of the method for preparing a light-emitting device provided in an embodiment of the present application.

[0060] Reference numerals:

[0061] Light emitting device 100 ; first electrode 10 ; functional layer 101 ; second electrode 20 ; light emitting layer 30 ; first carrier functional layer 40 ; second carrier functional layer 50 ; passivation layer 60 . DETAILED DESCRIPTION

[0062] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0063] In this application, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. In addition, in the description of this application, the term "including" means "including but not limited to". The terms first, second, third, etc. are used only as labels and do not impose numerical requirements or establish an order.

[0064] In this application, "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0065] In the present application, "at least one" means one or more, and "plurality" means two or more. "One or several", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0066] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0067] In existing light-emitting devices, the material of the functional layer is often made of nanoparticles, which are small in size and have high surface energy. As the particle size of nanoparticles decreases, the number of surface atoms increases rapidly. This is due to the small particle size and the rapid increase in surface area. Due to the increase in the number of surface atoms, insufficient atomic coordination and high surface energy, these surface atoms have high activity, are extremely unstable, and are easy to combine with other atoms. When the particle size drops to 1nm, the proportion of surface atoms reaches more than about 90%, and almost all atoms are concentrated on the surface of nanoparticles. Due to the increase in the number of surface atoms of nanoparticles, insufficient surface atomic coordination and high surface energy, these atoms are easy to combine with other atoms and stabilize, so they have high chemical activity.

[0068] The high chemical activity of nanoparticles leads to more surface defects, which easily cause trap and detrap processes, reduce the luminous efficiency of the device and increase power consumption. At present, nanoparticles have many defects, and the luminous efficiency of light-emitting devices is low, which needs to be further improved. The technical solution of this application is as follows:

[0069] First, see Figures 1 to 7 The embodiment of the present application provides a light-emitting device 100, comprising: a first electrode 10, a light-emitting layer 30 and a second electrode 20 which are stacked, wherein the material of the light-emitting layer 30 comprises nanoparticles.

[0070] In some embodiments, the material of the light emitting layer 30 includes a first passivator.

[0071] In some embodiments, the light emitting device 100 further includes a first carrier functional layer 40 , wherein the first carrier functional layer 40 is disposed between the first electrode 10 and the light emitting layer 30 , and a material of the first carrier functional layer 40 includes a second passivator.

[0072] In some embodiments, the light-emitting device 100 also includes a first carrier functional layer 40 and a passivation layer 60, the first carrier functional layer 40 is arranged between the first electrode 10 and the light-emitting layer 30, the passivation layer 60 is arranged between the first carrier functional layer 40 and the light-emitting layer 30, and the material of the passivation layer 60 includes a passivation material.

[0073] In some embodiments, the first passivator, the second passivator and the passivation material are independently selected from one or more of AX compounds, the A is selected from R-COOH-, the R is H or an alkyl group with 1 to 5 main chain carbon atoms, and the X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements.

[0074] In some embodiments, the AX compound includes one or more of magnesium acetate, zinc acetate, and lithium acetate.

[0075] It can be understood that the nanoparticles have surface defects, and the passivating agent can be combined with the nanoparticles to passivate the surface defects of the nanoparticles.

[0076] The light-emitting device 100 provided in the present application comprises a material of a light-emitting layer 30 of the light-emitting device 100 comprising nanoparticles, a passivator comprising the light-emitting layer 30 or the first carrier functional layer 40 or the passivation layer 60 of the light-emitting device 100, wherein the passivator comprises an AX compound, wherein A is selected from R-COOH-, and X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements. The passivator can be combined with the nanoparticles, and the A ions in the passivator, as charge-rich Lewis bases, can be combined with defects containing positive charges on the surface of the nanoparticles to passivate the defects, improve the performance of the nanoparticles, and promote the luminescence of the nanoparticles; the X ions in the passivator have a small ion radius, and can effectively passivate defects containing negative charges on the surface of the nanoparticles, further reduce the power consumption of the light-emitting device 100, improve the luminescence efficiency of the light-emitting device 100, and extend the service life of the light-emitting device 100.

[0077] In some embodiments, the first carrier functional layer 40 is a hole functional layer or an electron functional layer.

[0078] In some embodiments, the mass ratio of the first passivator to the nanoparticles is 1:(1-5), for example, 1:(1.2-4.5), 1:(1.5-4.2), 1:(1.8-4), 1:(2-3.5), 1:(2.5-3), etc. Within the mass ratio range, the first passivator is beneficial to effectively passivate the defects of the luminescent material and improve the luminescent performance of the luminescent layer 30.

[0079] In some embodiments, the average particle size of the nanoparticles is 5 nm to 15 nm, for example, 6 nm to 14 nm, 7 nm to 13 nm, 8 nm to 12 nm, 9 nm to 11 nm, 10 nm to 10.5 nm, etc.

[0080] In some embodiments, the thickness of the light emitting layer 30 is 10 nm to 20 nm, for example, 11 nm to 19 nm, 12 nm to 18 nm, 13 nm to 17 nm, 14 nm to 16 nm, 15 nm to 15.5 nm, etc.

[0081] In some embodiments, the nanoparticles include quantum dots, and the quantum dots include one or more of single structure quantum dots, core-shell structure quantum dots, and perovskite semiconductor materials.

[0082] The material of the single structure quantum dots, the core material of the core-shell structure quantum dots and the shell material of the core-shell structure quantum dots can be respectively selected from but not limited to one or more of the group II-VI compounds, group IV-VI compounds, group III-V compounds and group I-III-VI compounds. The II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe. The IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The III-V group compound includes one or more of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb. The I-III-VI group compound includes one or more of CuInS2, CuInSe2 and AgInS2.

[0083] As an example, the core-shell structured quantum dots include one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS.

[0084] The perovskite semiconductor material includes a doped or undoped inorganic perovskite semiconductor, or an organic-inorganic hybrid perovskite semiconductor. The inorganic perovskite semiconductor has a general structural formula of AMX3, wherein A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion selected from Cl - Br - ,I - The general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, wherein B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or

[0085] [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion selected from Cl - Br - ,I - One or more of the .

[0086] In some embodiments, the material of the first carrier functional layer 40 further includes a first carrier functional material.

[0087] In some embodiments, the mass ratio of the second passivator to the first carrier functional material is 1:(2-10), for example, 1:(2.5-9.5), 1:(3-9), 1:(3.5-8.5), 1:(4-8), 1:(5-6), etc. Within the mass ratio range, the second passivator on the surface of the first carrier functional layer 40 in contact with the light-emitting layer 30 can passivate the surface defects of the quantum dots in contact with it, that is, passivate the defects of the quantum dots of the light-emitting layer 30 close to the surface of the first carrier functional layer 40, and improve the luminescence performance of the light-emitting layer 30.

[0088] In some embodiments, the light emitting device 100 further includes a second carrier functional layer 50 , and the second carrier functional layer 50 is disposed between the light emitting layer 30 and the second electrode 20 .

[0089] In some embodiments, the first carrier functional layer 40 is an electron functional layer, and the second carrier functional layer 50 is a hole functional layer.

[0090] In some other embodiments, the first carrier functional layer 40 is a hole functional layer, and the second carrier functional layer 50 is an electron functional layer.

[0091] It should be noted that the material of the electronic functional layer 50 also has surface defects. When the electronic functional layer 50 contains a passivator, the passivator can also passivate some of the surface defects of the electronic functional material.

[0092] In some embodiments, the electronic functional layer includes one or more of an electron injection layer and an electron transport layer.

[0093] In some embodiments, the hole functional layer includes one or more of a hole injection layer and a hole transport layer.

[0094] In some embodiments, the thickness of the electronic functional layer is 30 nm to 50 nm, for example, 32 nm to 48 nm, 33 nm to 46 nm, 35 nm to 45 nm, 36 nm to 42 nm, 38 nm to 40 nm, etc.

[0095] In some embodiments, the thickness of the hole functional layer is 10 nm to 30 nm, for example, 12 nm to 28 nm, 15 nm to 26 nm, 16 nm to 25 nm, 18 nm to 23 nm, 20 nm to 22 nm, etc.

[0096] In some embodiments, the material of the electronic functional layer includes one or more of doped or undoped semiconductor particles, quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds; the semiconductor particles include one or more of zinc oxide, barium oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, tungsten sulfide, copper sulfide, zinc selenide, indium phosphide, gallium phosphide, and barium titanate; and the doped elements include one or more of indium, gallium, aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium.

[0097] Furthermore, the average particle size of the semiconductor particles is 2nm to 10nm, for example, 2.5nm to 9.5nm, 3nm to 9nm, 4nm to 8nm, 5nm to 7nm, 6nm to 6.5nm, etc.

[0098] In some embodiments, the material of the hole functional layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tri(N-carbazolyl)-triphenylamine, 4,4',4'-tri(carbazol-9-yl)triphenylamine, Amine, trichloroisocyanuric acid, terbium-doped phosphate-based green luminescent materials, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylenevinylene), poly(phenylenevinylene), poly[2-methoxy-5-(2-ethylhexyloxy)- 1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amines, polynuclear aromatic tertiary amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N' - one or more of diphenylbenzidine, spiro NPB, nano-polycrystalline diamond, microcrystalline cellulose and tetracyanoquinodimethane, doped graphene, undoped graphene, transition metal oxides, transition metal sulfides, transition metal tin compounds, doped or undoped zinc oxide, barium oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, lithium zinc oxide, indium tin oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, tungsten sulfide, copper sulfide, zinc selenide, indium phosphide, gallium phosphide, copper indium sulfide, copper gallium sulfide, barium titanate, quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds.

[0099] It can be understood that the passivation material on the surface of the passivation layer 60 in contact with the light-emitting layer 30 can passivate the defects on the surface of the nanoparticles in contact with it, that is, passivate the defects of the nanoparticles on the surface of the light-emitting layer 30 close to the passivation layer 60, thereby improving the luminescence performance of the light-emitting layer 30.

[0100] In some embodiments, the thickness of the passivation layer 60 is 0.01 nm to 5 nm, for example, 0.1 nm to 4.5 nm, 0.5 nm to 4 nm, 1 nm to 3.5 nm, 1.5 nm to 3 nm, 2 nm to 2.5 nm, etc.

[0101] It should be noted that when the first carrier functional layer 40 is an electronic functional layer, the passivation material close to the light emitting layer 30 can passivate the defects of the nanoparticles, and the passivation material close to the electronic functional layer can also passivate the defects of the electronic functional material.

[0102] In some embodiments, the materials of the first electrode 10 and the second electrode 20 include one or more of metal, carbon material and metal oxide respectively; the metal includes one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb and Mg; the carbon material includes one or more of graphite, carbon nanotubes, graphene and carbon fiber; the metal oxide includes a metal oxide electrode or a composite electrode with a metal sandwiched between doped or undoped transparent metal oxides, the material of the metal oxide electrode includes one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3 and AMO, and the composite electrode includes one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2 and TiO2 / Al / TiO2. Here, “ / ” represents a stacked structure. For example, AZO / Ag / AZO represents a composite electrode including an AZO layer, an Ag layer and an AZO layer stacked in sequence.

[0103] In some embodiments, the thickness of the first electrode 10 is 30 nm to 40 nm, for example, 31 nm to 39 nm, 32 nm to 38 nm, 33 nm to 37 nm, 34 nm to 36 nm, 35 nm to 35.5 nm, etc.

[0104] In some embodiments, the thickness of the second electrode 20 is 30 nm to 40 nm, for example, 31 nm to 39 nm, 32 nm to 38 nm, 33 nm to 37 nm, 34 nm to 36 nm, 35 nm to 35.5 nm, etc.

[0105] Second, see Figure 8 The present application also provides a method for preparing a light emitting device 100, comprising:

[0106] S11, providing a light-emitting device preform, wherein the light-emitting device preform comprises a first electrode 10;

[0107] S12, forming a functional layer 101 on the light emitting device preform;

[0108] S13 , forming a second electrode 20 on the functional layer 101 to obtain the light emitting device 100 .

[0109] In S12:

[0110] In some embodiments, the S12 includes: forming a light-emitting layer 30 on the first electrode 10 , including: providing nanoparticles and a first passivator, and disposing the nanoparticles and the first passivator on the first electrode 10 to form the light-emitting layer 30 .

[0111] In some embodiments, the S12 includes: forming a first carrier functional layer 40 on the first electrode 10 , including: providing a first carrier functional material and a second passivator, and arranging the first carrier functional material and the second passivator on the first electrode 10 to form the first carrier functional layer 40 .

[0112] In some embodiments, the S12 includes: the light-emitting device preform also includes a light-emitting layer 30 arranged on the first electrode 10, and a first carrier functional layer 40 is formed on the light-emitting layer 30, including: providing a first carrier functional material and a second passivator, and arranging the first carrier functional material and the second passivator on the light-emitting layer 30 to form the first carrier functional layer 40.

[0113] In some embodiments, the S12 includes: the light-emitting device preform also includes a first carrier functional layer 40 arranged on the first electrode 10, and a passivation layer 60 is formed on the first carrier functional layer 40, including: providing a passivation material, and arranging the passivation material on the first carrier functional layer 40 to form a passivation layer 60.

[0114] In some embodiments, the S12 includes: the light-emitting device preform also includes a light-emitting layer 30 disposed on the first electrode 10, and a passivation layer 60 is formed on the light-emitting layer 30, including: providing a passivation material, disposing the passivation material on the light-emitting layer 30, and forming a passivation layer 60.

[0115] In some embodiments, the first passivator, the second passivator and the passivation material are independently selected from one or more of AX compounds, the A is selected from R-COOH-, the R is H or an alkyl group with 1 to 5 main chain carbon atoms, and the X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements.

[0116] It can be understood that the method for forming the functional layer 101 can adopt conventional technical means in the art.

[0117] In at least one embodiment, the method for forming the light-emitting layer 30 is a solution method, including: mixing the nanoparticles, the first passivator and the first solvent to obtain a first dispersion, and disposing the first dispersion on the light-emitting device preform to form the light-emitting layer 30.

[0118] In some embodiments, the first solvent includes one or more of ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0119] In some embodiments, in the first dispersion, the mass concentration of the nanoparticles is 5 mg / mL to 20 mg / mL, for example, 6 mg / mL to 18 mg / mL, 7 mg / mL to 16 mg / mL, 8 mg / mL to 15 mg / mL, 9 mg / mL to 14 mg / mL, 10 mg / mL to 12 mg / mL, etc.

[0120] In some embodiments, in the first dispersion, the mass concentration of the first passivator is 2 mg / mL to 20 mg / mL, for example, 4 mg / mL to 18 mg / mL, 6 mg / mL to 16 mg / mL, 8 mg / mL to 15 mg / mL, 9 mg / mL to 14 mg / mL, 10 mg / mL to 12 mg / mL, etc.

[0121] In some embodiments, in the first dispersion, the mass ratio of the first passivator to the nanoparticles is 1:(1-5), for example, 1:(1.2-4.5), 1:(1.5-4.2), 1:(1.8-4), 1:(2-3.5), 1:(2.5-3), etc.

[0122] In at least one embodiment, the method for forming the first carrier functional layer 40 is a solution method, comprising: mixing the first carrier functional material, the second passivator and the second solvent to obtain a second dispersion, and disposing the second dispersion on the light-emitting device preform to form the first carrier functional layer 40.

[0123] In some embodiments, the second solvent includes one or more of ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0124] In some embodiments, in the second dispersion, the mass concentration of the first carrier functional material is 10 mg / mL to 50 mg / mL, for example, 12 mg / mL to 45 mg / mL, 15 mg / mL to 40 mg / mL, 18 mg / mL to 35 mg / mL, 20 mg / mL to 30 mg / mL, 22 mg / mL to 28 mg / mL, etc. Within the mass concentration range, the dispersion of the first carrier functional material is facilitated.

[0125] In some embodiments, in the second dispersion, the mass concentration of the second passivator is 2 mg / mL to 20 mg / mL, for example, 4 mg / mL to 18 mg / mL, 6 mg / mL to 16 mg / mL, 8 mg / mL to 15 mg / mL, 9 mg / mL to 14 mg / mL, 10 mg / mL to 12 mg / mL, etc.

[0126] In some embodiments, in the second dispersion, the mass ratio of the second passivator to the first carrier functional material is 1:(2-10), for example, it can be 1:(2.5-9.5), 1:(3-9), 1:(3.5-8.5), 1:(4-8), 1:(5-6), etc.

[0127] It can be understood that the formation of the passivation layer 60 can adopt conventional techniques in the art, such as chemical methods or physical methods. Among them, the chemical method includes chemical vapor deposition, continuous ion layer adsorption and reaction, anodization, electrolytic deposition, and coprecipitation. The physical method includes physical coating and solution method, among which the physical coating method includes: thermal evaporation coating, electron beam evaporation coating, magnetron sputtering, multi-arc ion coating, physical vapor deposition, atomic layer deposition, pulsed laser deposition, etc.; the solution method can be spin coating, printing, inkjet printing, scraping, printing, dip-pull, immersion, spraying, rolling, casting, slit coating, and strip coating.

[0128] In at least one embodiment, the method for forming the passivation layer 60 is a solution method, which specifically includes providing a passivation material, dissolving the passivation material in a third solvent to obtain a passivation material solution, and disposing the solution on the light emitting device preform to form the passivation layer 60 .

[0129] In some embodiments, the third solvent includes one or more of ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0130] In some embodiments, in the passivation material solution, the mass concentration of the passivator is 2 mg / mL to 20 mg / mL, for example, 4 mg / mL to 18 mg / mL, 6 mg / mL to 16 mg / mL, 8 mg / mL to 15 mg / mL, 9 mg / mL to 14 mg / mL, 10 mg / mL to 12 mg / mL, etc.

[0131] It can be understood that in some embodiments, the fourth solvent is volatile, and after the passivation layer 60 is formed, other film layers can be directly disposed on its surface.

[0132] In some other embodiments, after forming the passivation layer 60, annealing is further included. Further, the annealing temperature is 80°C to 160°C, for example, 85°C to 155°C, 90°C to 150°C, 100°C to 145°C, 105°C to 130°C, 110°C to 120°C, etc.

[0133] The annealing time is 5 min to 60 min, for example, 8 min to 55 min, 10 min to 50 min, 12 min to 45 min, 15 min to 22 min, 18 min to 20 min, etc.

[0134] Thus, within the time range of annealing and temperature, it is beneficial to fully remove the fourth solvent and promote the beneficial properties of the passivating agent.

[0135] The first electrode 10 , the first carrier functional layer 40 , the light emitting layer 30 , and the second electrode 20 are described above and will not be described in detail herein.

[0136] In a third aspect, the present application further provides a display device, which includes the light-emitting device 100 described above.

[0137] The display device can be any electronic product with a display function, including but not limited to smart phones, tablet computers, laptops, digital cameras, digital video cameras, smart wearable devices, smart weighing electronic scales, car displays, televisions or e-book readers, among which smart wearable devices can be, for example, smart bracelets, smart watches, virtual reality (VR) helmets, etc.

[0138] The present application is described in detail below through specific embodiments. The following embodiments are only partial embodiments of the present application and are not limitations of the present application.

[0139] Example 1

[0140] This embodiment provides a light emitting device, and the preparation method is as follows:

[0141] Providing an ITO glass, cleaning the ITO glass with a cleaning agent to remove stains on the surface, then ultrasonically cleaning the ITO glass with deionized water, isopropyl acetone, acetone and deionized water for 20 minutes respectively, and then drying with nitrogen to obtain an ITO anode with a thickness of 30 nm;

[0142] A TFB solution with a concentration of 8 mg / mL was placed on the ITO anode and spin-coated at a speed of 5000 rpm for 30 seconds, followed by annealing at a temperature of 150°C for 15 minutes to obtain a 30 nm hole functional layer;

[0143] 120 mg of quantum dots with CdZnSeS as core and ZnS as shell and 60 mg of passivating agent magnesium acetate were dissolved in n-octane to prepare a quantum dot solution with a concentration of 12 mg / mL. The quantum dot solution was placed on the hole functional layer and spin-coated at a speed of 2000 rpm for 30 seconds. The coating was annealed at 100°C for 60 minutes to obtain a 15 nm light-emitting layer.

[0144] 100 mL of 30 mg / mL ZnO ethanol dispersion was placed on the light-emitting layer and spin-coated at a speed of 3000 rpm for 30 seconds, followed by annealing at 80° C. for 30 minutes to form an electronic functional layer with a thickness of 30 nm.

[0145] On the electronic functional layer, aluminum is evaporated, and the vacuum degree is not higher than 3x10 -4 Pa, speed 1 angstrom / second, time 100s, thickness 10nm, silver evaporation, vacuum degree not higher than 3x10 -4 Pa, speed 1 Å / s, time 200 s, thickness 20 nm, to obtain a cathode;

[0146] Packaging to obtain a light-emitting device.

[0147] Example 2

[0148] This embodiment is substantially the same as the embodiment 1, except that the preparation method of the electronic functional layer in this embodiment is as follows: 30 mg ZnO and 5 g of a passivating agent, magnesium acetate, are dissolved in ethanol to prepare an electronic functional material dispersion having a ZnO concentration of 30 mg / mL, which is disposed on a cathode and spin-coated at a speed of 3000 rpm for 30 seconds, and annealed at 100° C. for 60 minutes to form an electronic functional layer having a thickness of 30 nm;

[0149] The preparation method of the light-emitting layer is as follows: dissolve quantum dots with CdZnSeS as the core and ZnS as the shell in n-octane to prepare a quantum dot solution with a concentration of 15 mg / mL; use a pipette to absorb 45 μL, drop it on the hole functional layer, and spin coat it at a speed of 3500 rpm for 45 seconds, followed by annealing at a temperature of 120°C for 12 minutes to obtain a 20 nm quantum dot light-emitting layer.

[0150] Example 3

[0151] This embodiment is basically the same as the embodiment 1, except that the preparation method of the hole functional layer in this embodiment is as follows: 30 mg TFB and 5 g of passivating agent magnesium acetate are dissolved in N,N-dimethylformamide to prepare a hole functional material dispersion with a TFB concentration of 30 mg / mL, which is set on the anode and spin-coated at a speed of 3000 rpm for 30 seconds, and annealed at 100° C. for 60 minutes to form a hole functional layer with a thickness of 30 nm;

[0152] The preparation method of the light-emitting layer is as follows: dissolve quantum dots with CdZnSeS as the core and ZnS as the shell in n-octane to prepare a quantum dot solution with a concentration of 15 mg / mL; use a pipette to absorb 45 μL, drop it on the hole functional layer, and spin coat it at a speed of 3500 rpm for 45 seconds, followed by annealing at a temperature of 120°C for 12 minutes to obtain a 20 nm quantum dot light-emitting layer.

[0153] Example 4

[0154] This embodiment is basically the same as embodiment 1, except that in this embodiment, magnesium acetate is provided, dissolved in ethanol, and configured as a 10 mg / mL passivating agent solution, which is disposed on the light-emitting layer and annealed at 100° C. for 30 min to obtain a 2 nm passivating layer;

[0155] The preparation method of the light-emitting layer is as follows: dissolve quantum dots with CdZnSeS as the core and ZnS as the shell in n-octane to prepare a quantum dot solution with a concentration of 15 mg / mL; use a pipette to absorb 45 μL, drop it on the hole functional layer, and spin coat it at a speed of 3500 rpm for 45 seconds, followed by annealing at a temperature of 120°C for 12 minutes to obtain a 20 nm quantum dot light-emitting layer.

[0156] Example 5

[0157] This embodiment is substantially the same as embodiment 1, except that in this embodiment, magnesium acetate is provided, dissolved in ethanol, and configured as a 10 mg / mL passivating agent solution, which is disposed on the hole functional layer and annealed at 100° C. for 30 min to obtain a 2 nm passivating layer;

[0158] The preparation method of the light-emitting layer is as follows: dissolve quantum dots with CdZnSeS as the core and ZnS as the shell in n-octane to prepare a quantum dot solution with a concentration of 15 mg / mL; use a pipette to absorb 45 μL, drop it on the hole functional layer, and spin coat it at a speed of 3500 rpm for 45 seconds, followed by annealing at a temperature of 120°C for 12 minutes to obtain a 20 nm quantum dot light-emitting layer.

[0159] Example 6

[0160] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the passivating agent magnesium acetate is replaced by zinc acetate.

[0161] Example 7

[0162] This embodiment is basically the same as Embodiment 1, except that in this embodiment, the passivating agent magnesium acetate is replaced by lithium acetate.

[0163] Example 8

[0164] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, 120 mg of quantum dots and 120 mg of passivating agent are mixed.

[0165] Example 9

[0166] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, 120 mg of quantum dots and 24 mg of passivating agent are mixed.

[0167] Example 10

[0168] This embodiment is substantially the same as Embodiment 2, except that, in this embodiment, 30 mg of ZnO and 15 mg of a passivating agent are mixed.

[0169] Embodiment 11

[0170] This embodiment is substantially the same as Embodiment 2, except that, in this embodiment, 30 mg of ZnO and 3 mg of passivating agent are mixed.

[0171] Example 12

[0172] This embodiment is substantially the same as Embodiment 4, except that in this embodiment, the thickness of the second passivation layer is 5 nm.

[0173] Example 13

[0174] This embodiment is substantially the same as Embodiment 4, except that in this embodiment, the thickness of the second passivation layer is 0.01 nm.

[0175] Comparative Example 1

[0176] This comparative example is basically the same as Example 1, except that the preparation method of the light-emitting layer in this comparative example is as follows: dissolving quantum dots having CdZnSeS as the core and ZnS as the shell in n-octane to prepare a quantum dot solution having a concentration of 15 mg / mL; aspirating 45 μL with a pipette, dropping it on the hole functional layer, and spin coating at a speed of 3500 rpm for 45 s, followed by annealing at a temperature of 120° C. for 12 min to obtain a 20 nm quantum dot light-emitting layer.

[0177] Comparative Example 2

[0178] This comparative example is substantially the same as comparative example 1, except that in this comparative example, magnesium acetate is replaced by tetrabutylammonium acetate.

[0179] Comparative Example 3

[0180] This comparative example is substantially the same as comparative example 1, except that magnesium acetate is replaced by triazine zinc in this comparative example.

[0181] Comparative Example 4

[0182] This comparative example is substantially the same as comparative example 4, except that magnesium acetate is replaced by sodium acetate in this comparative example.

[0183] The maximum external quantum efficiency and lifespan T95@1000nit tests were performed on the quantum dot light-emitting diodes in Examples 1 to 13 and the comparative example, and the test results were obtained and are shown in Table 1.

[0184] Among them, the maximum external quantum efficiency detection method is: measured by LabView controlling the efficiency test system built by QE PRO spectrometer, Keithley2400, and Keithley 6485, with a driving current of 2mA;

[0185] The test method for life span T50@100nit is: using a 128-channel life span test system customized by Guangzhou New Vision Company. The system architecture is a constant voltage and constant current source to drive QLED, test the change in voltage or current, and the photodiode detector and test system test the brightness (photocurrent) change of QLED. The brightness meter test calibrates the brightness (photocurrent) of QLED to obtain the time it takes for the initial brightness of the light-emitting diode to decay to 95%, and the driving current is 2mA; T95@1000nit refers to the time it takes for the initial brightness of the device to decay to 95%, and it is converted to the aging time at 1000nit.

[0186] Table 1

[0187]

[0188]

[0189] From Table 1, we can see that:

[0190] It can be seen from Examples 1 to 5 and Comparative Example 1 that doping the functional layer of the light-emitting device with a magnesium acetate passivator can effectively passivate the defects of the quantum dots and improve the luminous efficiency of the light-emitting device. Extend the service life of the light-emitting device, wherein the magnesium acetate passivator is added as a layer of passivator in the electronic functional layer and the light-emitting layer, which has the best effect on improving the performance of the light-emitting device;

[0191] It can be seen from Example 1, Examples 6 to 7 and Comparative Examples 1 to 3 that the material replacing the passivating agent has no significant effect on the light-emitting device compared with Example 1, and its luminous efficiency and service life are significantly higher than the light-emitting devices of Comparative Examples 1 to 3. Magnesium acetate, lithium acetate and zinc acetate are introduced into the light-emitting device as passivating agents, and the effect on the light-emitting device is better than tetrabutylammonium acetate and triazine zinc. Magnesium acetate as a passivating agent improves the performance of the light-emitting device most significantly;

[0192] It can be seen from Example 1, Examples 8 to 9 and Comparative Example 1 that within the mass ratio range of quantum dots and passivating agent provided in the present application, the passivating agent can effectively passivate the defects of quantum dots, improve the luminous efficiency of the light-emitting device, and extend the service life of the light-emitting device;

[0193] It can be seen from Example 2, Examples 10 to 11 and Comparative Example 1 that within the mass ratio range of the electronic functional layer material and the passivator provided in the present application, the electronic functional layer is disposed adjacent to the light-emitting layer, and the passivator can passivate the surface defects of the quantum dots, thereby improving the luminous efficiency of the light-emitting device and extending the service life of the light-emitting device;

[0194] It can be seen from Example 4, Examples 12 to 13, Comparative Examples 1 and 4 that adding a passivation layer between the electronic functional layer and the light-emitting layer can significantly improve the luminous efficiency of the light-emitting device, wherein the thickness of the passivation layer has little effect on the light-emitting device; using zinc acetate as a passivating agent is more effective than introducing sodium acetate in Comparative Example 4, and can significantly extend the service life of the light-emitting device.

[0195] The light-emitting device and its preparation method, and the display device provided in the embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A light emitting device, characterized in that: include: A first electrode, a light-emitting layer and a second electrode are stacked, wherein the material of the light-emitting layer includes nanoparticles; The material of the light-emitting layer includes a first passivator; or The light emitting device further comprises a first carrier functional layer, the first carrier functional layer is arranged between the first electrode and the light emitting layer, and the material of the first carrier functional layer comprises a second passivator; or The light emitting device further comprises a first carrier functional layer and a passivation layer, wherein the first carrier functional layer is arranged between the first electrode and the light emitting layer, the passivation layer is arranged between the first carrier functional layer and the light emitting layer, and the material of the passivation layer comprises a passivation material; The first passivator, the second passivator and the passivation material are independently selected from one or more of AX compounds, the A is selected from R-COOH-, the R is H or an alkyl group with 1 to 5 main chain carbon atoms, and the X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements.

2. The light emitting device according to claim 1, characterized in that: The AX compound includes one or more of magnesium acetate, zinc acetate, and lithium acetate; and / or The first carrier functional layer is a hole functional layer or an electron functional layer.

3. The light emitting device according to claim 1, characterized in that: The mass ratio of the first passivator to the nanoparticles is 1:(1-5); or The material of the first carrier functional layer also includes a first carrier functional material, and the mass ratio of the second passivator to the first carrier functional material is 1:(2-10).

4. The light emitting device according to claim 1, characterized in that: The light emitting device further comprises a second carrier functional layer, which is arranged between the light emitting layer and the second electrode, and is an electron functional layer or a hole functional layer.

5. The light emitting device according to claim 4, characterized in that: The nanoparticles include quantum dots, and the materials of the quantum dots include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, Sn STe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, Al Sb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs , InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, I One or more of nAlNSb, InAlPAs, InAlPSb, CuInS2, CuInSe2, AgInS2, CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS, InP / ZnSe / ZnS, AMX3 and BMX3, wherein A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2 + ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion selected from Cl - Br - ,I - One or more of; B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n ≥ 2; and / or The material of the electronic functional layer includes one or more of doped or undoped semiconductor particles, quinoxaline compounds, imidazole compounds, triazine compounds, fluorene compounds, and hydroxyquinoline compounds; the semiconductor particles include one or more of zinc oxide, barium oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, tungsten sulfide, copper sulfide, zinc selenide, indium phosphide, gallium phosphide, and barium titanate; the doped elements include one or more of indium, gallium, aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium; and / or The material of the hole functional layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tri(N-carbazolyl)-triphenylamine, 4,4',4'-tri(carbazol-9-yl)triphenylamine, trichloroisocyanurate, Acid, terbium-doped phosphate-based green luminescent materials, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene [vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amines, polynuclear aromatic tertiary amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N'-diphenyl Benzidine, spiro NPB, nano-polycrystalline diamond, microcrystalline cellulose and tetracyanoquinodimethane, doped graphene, undoped graphene, transition metal oxides, transition metal sulfides, transition metal tin compounds, doped or undoped zinc oxide, barium oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, lithium zinc oxide, indium tin oxide, cadmium sulfide, zinc sulfide, molybdenum sulfide, tungsten sulfide, copper sulfide, zinc selenide, indium phosphide, gallium phosphide, copper indium sulfide, copper gallium sulfide, barium titanate, quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, hydroxyquinoline compounds, or one or more thereof; and / or The materials of the first electrode and the second electrode independently include one or more of metal, carbon material and metal oxide; the metal includes one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb and Mg; the carbon material includes one or more of graphite, carbon nanotubes, graphene and carbon fiber; the metal oxide includes a metal oxide electrode or a composite electrode with a metal sandwiched between doped or undoped transparent metal oxides, the material of the metal oxide electrode includes one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3 and AMO, and the composite electrode includes one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2 and TiO2 / Al / TiO2.

6. The light emitting device according to claim 4, characterized in that: The average particle size of the nanoparticles is 5nm to 15nm; and / or The thickness of the light-emitting layer is 10 nm to 20 nm; and / or The thickness of the electronic functional layer is 30nm to 50nm; and / or The thickness of the hole functional layer is 10nm to 30nm; and / or The thickness of the passivation layer is 0.01 nm to 5 nm; and / or The thickness of the first electrode and the second electrode are independently 30 nm to 40 nm.

7. A method for preparing a light emitting device, characterized in that: include: Providing a light-emitting device preform, wherein the light-emitting device preform comprises a first electrode; forming a light-emitting layer on the first electrode, comprising: providing nanoparticles and a first passivator, and arranging the nanoparticles and the first passivator on the first electrode to form the light-emitting layer; or Forming a first carrier functional layer on the first electrode, comprising: providing a first carrier functional material and a second passivator, and arranging the first carrier functional material and the second passivator on the first electrode to form the first carrier functional layer; or The light emitting device preform further includes a light emitting layer disposed on the first electrode, and forming a first carrier functional layer on the light emitting layer includes: providing a first carrier functional material and a second passivator, and disposing the first carrier functional material and the second passivator on the light emitting layer to form the first carrier functional layer; or The light emitting device preform further includes a first carrier functional layer disposed on the first electrode, and forming a passivation layer on the first carrier functional layer includes: providing a passivation material, and disposing the passivation material on the first carrier functional layer to form the passivation layer; or The light emitting device preform further comprises a light emitting layer disposed on the first electrode, and forming a passivation layer on the light emitting layer comprises: providing a passivation material, and disposing the passivation material on the light emitting layer to form a passivation layer; Wherein, the first passivator, the second passivator and the passivation material are independently selected from one or more of AX compounds, the A is selected from R-COOH-, the R is H or an alkyl group with 1 to 5 main chain carbon atoms, and the X is selected from lithium ions, metal ions of group IIA elements or metal ions of group IIB elements; A second electrode is formed on the first carrier functional layer, the light emitting layer or the passivation layer to obtain a light emitting device.

8. The preparation method according to claim 7, characterized in that: The AX compound includes one or more of magnesium acetate, zinc acetate, and lithium acetate; and / or The first carrier functional layer is a hole functional layer or an electron functional layer.

9. The preparation method according to claim 7, characterized in that: The forming of the light-emitting layer comprises: mixing the nanoparticles, the first passivator and the first solvent to obtain a first dispersion, and disposing the first dispersion on the light-emitting device preform to form the light-emitting layer; or The forming of the first carrier functional layer comprises: mixing the first carrier functional material, the second passivator and the second solvent to obtain a second dispersion, and disposing the second dispersion on the light emitting device preform to form the first carrier functional layer; or The forming of the passivation layer comprises: providing a passivation material, dissolving the passivation material in a third solvent to obtain a passivation material solution, and disposing the passivation material solution on the light emitting device preform to form the passivation layer.

10. The preparation method according to claim 9, characterized in that: In the first dispersion, the mass concentration of the nanoparticles is 5 mg / mL to 20 mg / mL; and / or In the first dispersion, the mass concentration of the first passivator is 2 mg / mL to 20 mg / mL; and / or In the first dispersion, the mass ratio of the first passivator to the nanoparticles is 1:(1-5); and / or In the second dispersion, the mass concentration of the first carrier functional material is 10 mg / mL to 50 mg / mL; and / or In the second dispersion, the mass concentration of the second passivating agent is 5 mg / mL to 20 mg / mL; and / or In the second dispersion, the mass ratio of the second passivator to the first carrier functional material is 1:(2-10); and / or In the passivation material solution, the mass concentration of the passivation material is 2 mg / mL to 20 mg / mL; and / or The first solvent, the second solvent, and the third solvent respectively include one or more of ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

11. The preparation method according to claim 8, characterized in that: After the passivation layer is formed, annealing is further performed. The annealing temperature is 80° C. to 160° C. and the annealing time is 5 min to 60 min.

12. A display device, characterized in that: A light-emitting device comprising the light-emitting device as claimed in any one of claims 1 to 6, or a light-emitting device manufactured by the manufacturing method as claimed in any one of claims 7 to 11.

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